Alkylalkoxyalkylhydrazones



United States Patent 3 091,611 ALKYLALKOXYALKYLHYDRAZONES John C. Howard, Augusta, Ga., assignmto The Norwich Pharmaeal Company, a corporation of New York No Drawing. Filed Mar. 22, 1961, Ser. No. 97,442 8 Claims. (Cl. 260-240) This invention relates to organic synthesis and to a new class of organic compounds produced thereby. More particularly it is concerned with the synthesis of alkylalkoxyalkylhydrazones and with aldehyde alkylalkoxyalkylhydrazones which are useful as characterizing and therapeutic agents.

The aldehyde alkylalkoxyalkylhydrazones of this invention, which may be represented by the following general formula:

wherein R represents a -nitro-2-furyl or p-nitrophenyl group;

R represents an alkyl or substituted alkyl group;

R represents an alkyl group, and

R represents a S-nitro-Z-furyl, p-nitrophenyl or phenyl group;

can be readily synthesized by bringing together an aldehyde and an alkyl or substituted alkyl hydrazine in an alkanolic medium.

In accordance with this invention, compounds represented in Formula A can be prepared through the use of various forms of the hydrazine reactant; for example:

1) It can contain a free amino group; viz. H NNHR wherein R has the significance given above, in which case two moles of aldehyde reactant are provided for each mole of H NNHR or (2) It can be a hydrazone; for example, S-nitro-Z-furaldehyde methylhydrazone, in which case one mole of aldehyde reactant is provided for each mole of the hydrazone.

A schema illustrative of the synthesis of this invention may be depicted thusly:

R1 OR:

Ald BNNHR; 11,011 RCH=NIIH-R wherein R, R R and R have the significance ascribed above; Ald is benzaldehyde, S-nitro-Z-furaldehyde or pnitrobenzaldehyde; and B represents H or S-nitrofurfurylidene with the proviso that when Ald is benzaldehyde, B is S-nitrofurfurylidene and with the further proviso that when B is H the mole ratio of Ald to H NNHR is 2:1.

In the practice of this invention the hydrazine and the aldehyde can be added to the appropriate alkanol; for instance methanol, ethanol or isopropanol, and the mixture allowed to react. However, it is currently preferred to prepare a solution of the hydrazine in the appropriate alcohol and a solution of the aldehyde in the alcohol and add one to the other. In carrying out the reaction the presence of a mineral acid, such as hydrochloric, is desirable. To insure complete reaction, heat may be supplied to the reaction mixture. The aldehyde alkylalkoxyalkylhydrazone is readily recovered from the reaction mixture by filtration. 11: may be recrystallized from a suitable solvent such as methanol, ethanol, nitromethane, isopro panol or benzene or mixtures thereof.

Exemplary compounds prepared in accordance with this invention consist of:

S-nitro-Z-furaldehyde (oz-methoxy-5-nitrofurfuryl)methylhydrazone 5 nitro 2 furaldehyde (a -isopropoxy 5 nitrofurfuryl)methylhydrazone 5-nitro-2-furaldehyde (a-ethoxy-5-nitrofurfuryl)carbarnyl methylhydrazone 3,09 1,6 1 1 Patented May 28, 1963 5 nitro 2 -furalclehyde (a methoxylbenzyllmethylhyd-razone l 5-nitro-2-furaldehyde (e-methoxy-S-nitrofurfuryl Z-methoxycarbonyl) ethylhydrazone p Nitrobenzaldehyde (a methoxy p nitrobenzyl) methylhydrazone Such compounds are characterizing derivatives of the respective aldehyde. They are readily obtained, easily handled, crystalline substances possessing melting points within the range desired in identification procedures; viz., not so high as to require undue exposure to heat with possible decomposition; yet not so low as to require precaution in storage. They are relatively insoluble in common solvents at ordinary temperature but are sufficiently soluble at elevated temperature to permit facile recrystallization for the making of an analytical sample. They also possess individual spectral behavior permitting ultraviolet and infrared determinations to aid in their identification.

These compounds, particularly those containing the 5- nitrofuryl moiety, possess therapeutic properties. They are inhibitory to a wide range of infective organisms including bacteria and fungi such as E. 0011', S. typhosa, P. multocida, S. pyogenes, S. aureus, C. albicans, M. canis and N. asreroides. They may thus be used as the active ingredient in the formulation of pharmaceutical preparations such as creams, ointments, solutions, suppositories, and the like which may be employed to counteract and ameliorate local infective processes produced by organisms susceptible to them.

Those compounds containing the S-nitrofuryl moiety are effective agents in combatting parasitic infections caused by E. tenella and S. obvelam. When administered orally at a level of 0.022% by weight in the diet of poultry in- Eected with E. tenella, the predominant causative agent of cecal coccidiosis, mortality and morbidity due to that disease are effectively cornbatted.

Mice harboring a pinworm infection, S. obvelma, whose behavior and response parallels that of E. vermicularis, the pinworm frequently encountered in human medicine, are ridded of that organism by the oral administration of from about to 200 rug/kg. of these compounds.

These compounds are relatively nontoxic. As might be expected their toxicity varies, ranging in highest tolerated dose in mice from about 400 to about 2200 mgJkg.

In order that this invention may be readily understood and comprehended by those skilled in the art the following illustrative examples are briefly set forth:

EXAMPLE I A solution of 9.2 g. (0.20 m.) of methylhydrazine in 250 cc. of methyl alcohol is neutralized with 15 cc. of cone. l-ICl with cooling. This solution is added over a half-hour period to 70 g. (0.50 m.) of 5-nitro-2-furaldehyde in 500 cc. of methyl alcohol. After the addition the reaction mixture is stirred for an additional half-hour. The mixture is cooled; then filtered and the solid collected and washed Well with methyl alcohol and ether. The crude product weighs 47 g. (72% yield) and melts at 6 C. This may be recrystallized from methyl alcohol (l g./36 cc.) to give a melting point of -l C.

Analysis.Calc.: C, 44.45; H, 3.73; N, 17.28. Pd: C, 44.41, 44.48; H, 3.82, 3.90; N, 16.95.

EXAMPLE II 5 -N itro-Z-F uraldehyde (e-lsopr poxy-5-Nitrofurfaryl) Methylhydrazone A solution of 5.0 g. (0.108 m.) of methylhydrazine in 100 cc. of isopropyl alcohol is cooled and neutralized with 9 cc. of cone. HCl. Water (20 cc.) is then added to effect solution. This solution is added, dropwise with stirring to a solution of 45 g. (0.32 m.) of S-nitro-Z-furaldehyde in 700 cc. of isopropyl alcohol and 10 drops of cone. HCl. The mixture is stirred at room temperature for 30 min. and then cooled. The mixture is filtered and the solid washed with 200 cc. of cold isopropyl alcohol. The crude material weighs 32.7 g. (86% yield) and melts at 100-- 102 C. This may be recrystallized from 750 cc. of isopropyl alcohol to give 28.5 g. melting at l02-4 C.

Analysis.Calc.: C, 47.73; H, 4.59; N, 15.90. Fd.: C, 47.82; H, 4.65; N, 15.70, 16.07.

EXAMPLE III 5 -Nitr-2-F uraldehyde (u-EIhoxy-S-Nitrofurfuryl Ca rbamylmethylhydrazone Methyl hydrazinoacetate hydrochloride (50 g. or 0.356 m.) is dissolved in 125 g. of ammonium hydroxide and the solution allowed to stand at room temperature overnight. The excess ammonia and most of the water are removed at reduced pressure, and to the residue 100 cc. ethanol is added, followed by 42 g. (0.712 m.) of acetone. The insoluble inorganic salt was filtered and washed with 50 cc. ethanol. The alcoholic solution, which has been treated with charcoal, is added to 100 g. (0.712 m.) of nitro-Z-furaldehyde in 300 cc. ethanol and 50 drops of cone. HCl. The resulting mixture is an orange solution with a small amount of insoluble material which is filtered. The mother liquor upon cooling gives yellow crystals which are filtered and washed well with ethanol and ether. The crude material which weighs 43 g. may be recrystallized from a mixture of ethanol and nitromethane (1300 cc. of 6 to 1 mixture) to give the product melting at 1845.

Analysis.Calc.: C, 44.10; H, 3.97; N, 18.37. Fd.: C, 43.83; H, 4.07; N, 18.63.

Elli... 463 3990 A EXAMPLE IV 5 -Nitr'0-2-F umldehyde (a-Methoxybenzyl) Methylhydrazone S-nitro-Z-furaldehyde methylhydrazone (50.7 g. or 0.30 m.) is added in one portion to a mixture of 47.7 g. (0.45 m.) of benzaldehyde (distilled, B.P. 6475 at 11-25 mm.), 750 cc. of methyl alcohol and one drop of cone. HC], in a 2-1. flask fitted with a stirrer. The reaction mixture is warmed in a water bath at 50 for 30 min. until all the starting material dissolves and then is treated with charcoal and filtered. The product which precipitates as yellow crystals upon cooling is filtered and washed with a small amount of methyl alcohol and ether. This weighs 79 g. (91% yield) and may be recrystallized from methanol to give the product a melting at 107.5-85 C.

Analysis.Calc.: C, 58.12; H, 5.23; N, 14.53. Fd.: C, 58.05; H, 5.34; N, 14.66.

EXAMPLE V S-Nitro-Z-Furaldehyde (or-MethoxyJ-NitrofurfuryI) 2-Methorycarb0nyl Ethylhydrazone To 12 g. (0.078 mole) of methyl Z-hydrazinopropionate hydrochloride in 200 ml. of methanol is added 30 g. (0.21 mole) of S-nitro-Z-furaldehyde in 200 ml. of methanol. After standing for several minutes a yellow solid begins to precipitate. After 1 hour the precipitate is collected, washed with methanol and ether, and dried at room temperature. The yield is 17 g. (55%) M.P. 128130 which may be recrystallized from methanol to give an analytical sample melting at 130-131".

Analysis.Calcd. for C H N O C, 45.46; H, 4.07; N, 14.14. Found: C, 45.59; H, 4.20; N, 13.95.

4 EXAMPLE v1 p-Nitrobenzaldehyde(a-Methoxy-p-Nitrobenzyl) M eth ylhydrazone p-Nitrobenzaldehyde (23.65 g. or 0.157 m.) is suspended in 200 cc. methyl alcohol containing 20 drops of cone. hydrochloric acid. Methylhydrazine (3.44 g. or

0.0748 m.) in 50 cc. methyl alcohol is dropped in.

After the addition, the solution is heated on a steam bath for 10 min. and then treated with charcoal. Upon standing, an oil separates. A further quantity of methanol is added. Upon cooling, the alcoholic solution gives yellow crystals which are collected and washed with methyl alcohol. The crude product weighs 15.2 g. (59% yield).

Crystallization was carried out in methyl alcohol or a mixture of methyl alcohol and benzene to yield the product melting at l C.

Analysis for C H N O .Calc.: C, 55.81; H, 4.68; N,

16.27. Fd.: C, 55.95; H, 4.79; N, 16.35.

ER? 630 3690 A.

What is claimed is: 1. A compound of the formula:

R1 OR: RCH=NI ICHRs in which:

R represents a radical selected from the group consisting of 5-nitro-2-furyl and p-nitrophenyl;

R represents a radical selected from the group consisting of (lower)alkyl, carbamyl(lower)alkyl, and (lower)alkoxyc arbo nyl (lower) alkyl;

R represents a C -C alkyl group; and

R represents a radical selected from the group consisting of S-nitrofuryl, phenyl and p-nitrophenyl.

2. The compound 5-nitro-2-furaldehyde (a-methoXy-S- nitrofurfuryl) methylhydrazone of the formula:

...ljl..-.-iieiil..

3. The compound 5-nitro-2-furaldel1yde(a-isopropoxy- S-nitrofurfuryl)methylhydrazone of the formula:

UL (13H; mmortal 0m 0/ CH=NNOII 0/ N01 4. The compound 5-nitro-2-furaldehyde(a-ethoxy-5- nitrofiurfuryl)carbamylmethylhydrazone of the formula:

l mucoc zmocnnl om -on=N-Nhrr -i 0/ NO:

5. The compound 5-nitro-2-furaldehyde (a-methoxybenzyhmethylhydrazone of the formula:

I 111. Jorn 0m )-on=N-N-orr@ l onioooomr ln, 30m I om OHN-NCH NO: 0 o

7. The compound p-nitrobenzaldehyde(a-methoxy-pnitrobenzyl)methylhydrazone of the formula:

CH OCH:

8. A method of preparing an aldehyde (lower) alkyl (lower) alkoxy (lower) alkylhydrazone which comprises hydrazine derivative is a S-nitrofurfurylidene (lower) combining in a lower alkanol and in the presence of a alkylhydrazone.

mineral acid about 1 to 2 moles of an aldehyde selected t from the group consisting of S-nitro-Z-furaidehyde, benz- References Cited m the file of thls pa em aldehyde and p-nitrobenzaldehyde per mole of a hydra- 5 FOREIGN PATENTS zine derivative selected from the group consisting of a 180,357 Japan Sept. 21, 1949 (lower) alkyl hydrazine, a carbamyl (lower) alkyl hy- OTHER REFERENCES drazine, a (lower) alkoxycarbamyl (lower) alkyl hydrazine and a S-nitrofurfuryidene (lower) alkylhydrazone; Dannet et ai.: Chermsche B n Volume P g provided that where said aldehyde is benzaldehyde, said 10 8536 (1949). 

1. A COMPOUND OF THE FORMULA: 